there's a problem you will run into with this. Salt (a favorite of dips) has been around since before aquariums, and we have just adapted what we do to suit it best. Medications, on the other hand, have been formulated for a specific treatment regime in mind. If you go ahead with a concentrated bath, the fish might come out fine... or it might stress it beyond the point of toleration (and I think we all know how that ends).
I would go grab a $10 10g QT tank and a $3 sponge filter (if you don't have an air pump, it might be cheaper to grab a $10 Rio 50 power head and slap a sponge over the intake... same results) and run the recommended dosage.
To answer your original question, I can't give you procedure because I have never felt the need to test tried and true methods. www.fishyfarmacy.com has a great diagnosis chart. Should be the third or fourth link over at the top. Has a list of symptoms and possible causes, plus recommended treatments (all products they sell of course!), you might be able to find a dip alternative to some of these products that has been made for a bath.